Another Unscripted Car Crash on 'Transformers 3' Set

10/11/2010 4:50 PM PDT

There was more trouble on the Washington D.C. set of "Transformers 3" today -- when a cop car drove through the movie's perimeter and collided with one of the movie's main stars ... bright yellow Autobot Bumblebee!

A nearby shop owner tells TMZ there was a lot of police activity in the area right at the time of the accident due to a bomb scare. It is unclear if the cop car involved in the accident was part of that investigation.

UPDATE: D.C. police tell TMZ the cop car involved was part of the Explosives Ordinances Division. We're told the cop driving was taken to a nearby hospital.